Floor surface covering materials, such as carpets, and more particularly carpet tiles, typically comprise a traffic-bearing or wear face surface on a primary backing, such as a fibrous face surface, which has been woven, needle-punctured, fusion-bonded or otherwise secured to a primary backing layer or sheet, and a back surface to which is bonded one or more layers of solid or foam backing material. A solid backing material typically comprises a polyvinyl chloride backing material or a bitumen or atactic polypropylene backing layer, which are thermoplastic-type materials and which require different techniques in the coating process due the nature of the backing materials. Foam backing layers usually comprise a soft, resilient foam material, such as a polyvinyl chloride foam, a urethane foam or an elastomer latex-type foam, such as a styrene-butadiene-styrene rubber foam, to provide a resilient cushioning effect, and which foam is secured by an adhesive layer to the backing layer or directly to the back surface of the primary backing layer. The foam backing layer is selected to be resilient, i.e. elastomeric in properties, and to have a high compression strength and a low compression set, that is, the foam will upon compression rebound quickly or retain its original dimensions after repeated or prolonged use so as not to deform the face of the carpet, such as for example where chair or table legs are placed on the face surface of the carpet for short or extended time periods. Such floor surface coverings may also optionally have embossed back surfaces or have secondary backing layers, such as polyester or polypropylene layers, applied to the back surface of the floor surface material. The covering also may include for example continuous or discontinuous, pressure-sensitive adhesive material with or without a release sheet for securing the surface covering to the substrate to which it is going to be applied.
It is desirable to provide for a new and improved foam-containing floor surface covering material and method of preparation which employs foam material in the backing layer and to provide a lightweight, resilient, cushioned floor surface covering material, particularly a foam-containing, backed carpet tile.